Apparatus for grinding, smoothing, and polishing plate-glass.



E. BAGNALL.

APPARATUS FOR GRINDING, SMOOTHING, AND POLISHING PLATE GLASS;

APPLICATION FILED FEB. 3, 1913.

1,069,369, A Patented Aug,5, 1913.

3 SHEETSSHEET 1.

FIBI- WI%SSESI I I 6 z I INVENTOR E. BAGNALL.

APPARATUS FOR GRINDING, SMOOTHING. AND POLISHING PLATE GLAss.

APPLICATION FILED FEB..3. 1913.

1,069,369. Patented Aug 5, 1913.

3 SHEETS SHEET 2.

12 FIGZ- \hflTN fis'i fisj-; I I v 2 I: E :ZINVENTOR 04 JZW/MMJ/ 7 We Atty E. BAGNALL.

APPARATUS FOR GRINDING, SMOOTHING, AND POLISHING PLATE GLASS.

APPLICATION FILED FEB. 3, 1913.

1,069,369, Patented Augi5, 1913.

3 SHEETS-SHEET 3.

Atty Y UNITED STATES PATENT OFFICE.

EDWARD BAGNALL, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 ZOFFER PLATE GLASS MANUFACTURING COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPO- RATION OF WEST VIRGINIA.

Specification of Letters Patent.

Patented Aug. 5,1913.

Application filed February 8, 1913. Serial No. 745,794.

To all whom it may concern:

Be it known that I, EDWARD BAGNALL, a citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Aparatus for Grinding, Smoothing, and P01- lshing Plate-Glass, of which the following is a specification.

My invention relates to the class of apparatus for grinding, smoothing and polishing plate glass, and has for its object to provide, in a mechanism of this type, a rotatable supporting table for the glass, plates havin means for effecting holding suction by exhausting the air from the hollow interior of the table, such means being mounted to revolve with the table or its support-ing structure, together with other features of improvement and construction as shall be more fully hereinafter described.

In the drawings illustrating preferred forms of the invention Figure 1 is a vertical sectional view showing one form of apparatus constructed in accordance with the invention. Fig, 2 is a plan View of the supporting table, the upper plate structure being partly broken away to expose the vacuum cavity. Fig. 3 is an enlarged sectional detail view taken on the line III. III. of Fig. 2. Fig. 1 is a horizontal sectional View taken on the line IV. IV. of Fig. 1. Fig. 5 is a vertical sectional view of the upper portion of the table, similar to Fig. 1, but showing a modified arrangement and location of the air-exhausting or vacuum-creating mechanism.

My improved apparatus is designed to provide means for fixedly supporting and holding the plates of glass a upon the upper surface of the rotatable table A by means of air exhaustin mechanism, mounted upon and revoluble wlth the table, or its support, and arranged to exhaust the air from a cavity 1) between the upper and lower portions of said table. For the purpose of so providing such an air cavity, and preferably of as small volume as possible, the main body portion of the table is built of one or more main supporting plates 2, preferably in segmental shape, as indicated in Figs. 2 and 3 of the drawings, joined together by abutting flanges 3 and bolts 4 arranged radially, as shown, and having at suitable locations upwardly projecting supporting abutments 5, and preferably an annular upwardly projecting rim 6. Said rim is faced upon its upper surface, providing a seat bearing for an annular packing gland or strip 7 of rub her or other suitable material, upon which seats the annular edge 8 of the upper platesupporting table top 9, also preferably faced or surfaced. Said table top is also made of a plurality of segmental sections, as shown, secured together by radially arranged abutting flanges 10 and bolts 11 in the same general manner as plates 2. These plates are spaced apart by the intervening abutments 5 or in any other suitable manner, to provide a solid backing and maintaining support to insure the continuous level arrangement of the glass supporting table, and are rigidly secured to ether by suitable connecting bolts 12, pre erably countersunk in receiving. holes in the outer edge portion of the table top 9.

Intervening space I), as shown, is comparatively thin or narrow, whereby to facilitate the rapid exhaustion of the air by the pumping mechanism hereinafter described, and in order to provide proper clearance for the downwardly projecting flanges 10, while maintaining circulating communication through all portions of the cavity 6, the portions of plates 2 adjacent to flanges 3 are deflected downwardly at positions corresponding to the arrangement of flanges 10, providing, when together, a circulating com municating channel 13 for the air. The table, as thus constructed, is mounted for rotation upon the upper end of a supporting mast or column 14, to which it may be rotatably secured by a suitable key or other means, but preferably in such a manner that the entire table top may be lifted vertically by a crane or otherwise for transportation to any part of the plant, and for relocation on and attachment to another similar support ing column 14. In such case it will be understood thatthe pumping mechanism is uncoupled from the table in the construction shown in Fig. 1 by means of a union or other suitable joint.

The glass plates (1, which are usually rectangular, are laid over the table top 9, and slightly spaced above it by means of intervening continuous supporting strips 15 of rubber or other suitable material adapted to be sufiiciently compressed by atmospheric pressure to tightly pack the space between the edges of the glass plates a and the upper surface of the table top 9. Said table top is provided at suitable intervals with transverse apertures 16 for exhausting the air from beneath ea'ch particular plate, any exposed openings 16 not covered by the plate or plates being plugged or otherwise closed. By this arrangement when the plates are laid upon the table top and the air is exhausted from the space I), efiecting a complete or partial vacuum, the plates will be held firmly down upon the table top and in proper relation for action of the usual customary runners 1,7, 17.

Column 14 is mounted in any suitable manner at its lower end, as in a supporting step box 18, and is rotated in any convenient way, as by cables 19 engagingsheave 20 which is secured to the mast, and also preferably supported by its under side upon supporting rollers or wheels 21, as will be readily understood.

Mechanism for exhausting the air from cavity 6, as shown in Fig. 1, consists of a pump cylinder 22 havin a suitable plun er head 23 and stem 24 w ich is actuated loy any suitable prime mover, as an electric motor 25, through suitable gearing 26. These parts are supported on suitable brackets extending from the column 14, as shown. A reservoir 27 communicates with pump cylinder 22 by a communication 28, preferably provided with a check valve 29. Communication is made from reservoir 27 to the cavity 6 of the rotatable cable by means of a pipe 30 leading to the inner vacuum space, as shown, the pipe 30 being coupled together at any suitable point by a union or other coupling 31. Valves 32 and 33 are preferably incorporated in the line of pipe 30 at each side of the union coupling 31 to allow of tightly closing the pipes at one or both sides when such uncoupling operation is performed. A vacuum gage 34 may be connected with the interior space I) through the under plate 2, at any suitable point thereon, as clearly shown.

For the purpose of maintaining current to the motor 25-1 show circularly arranged main supply conductors 35, 36 communicating with a generator 37 by leads 38, 39, Fig. 4. The conductors 35 and 36 may be mounted in any suitable manner as upon brackets 40 within convenient reach of the column 14 in the manner of circular trolley wires. A trolley arm 41 projects outwardly from the column at one side and is provided with contact wheels 42 and 43 communicating through conductors 44 and 45 with motor 25,

osaaee thereby maintaining circuit to the motor, any suitable switch mechanism being employed, as indicated at 46, for controlling the supply. The various parts of the vacuum creating mechanism may also be support-ed from the under side of the main rotatable table, as shown in Fig. 5, to rotatewith it. In such construction, the pump cylinder 22 depends downwardly from an attaching base secured to the under side of the table, its plunger 23 and stem 24 being actuated from motor 25 through suitable gearing 26', the pump communicating by pipe sections 28' through check valve 29 with the reservoir 27, depending in the same manner from below the table.

Reservoir 27 communicates with the vacuum cavity 6 by pipe 30, couplin union 31 and valves 32, 33 being provided and operable in the same manner as above described. A vacuum gage 34 is also preferably connected with the vacuum cavity, as shown. By either of such constructions it will be seen that the pump mechanism is rotatably mounted with the rotatable table, and has direct communication with the table cavity. By this construction I avoid the necessity of the various complicated and usually imperfect connections between the rotatable table and stationary air exhausting mechanism, which have been heretofore employed.

My apparatus is especially eflicient in being capable of effecting a very rapid, direct exhaustion of the air from the vacuum cavity. It is comparatively simple and cheap in construction and installation; readily connected or disconnected, enabling the partly ground glass plates to be maintained in fixed position upon the table during its removal from one operating column to another; and provides an apparatus which is well and especially adapted for rapid, thorough grinding or polishing of plate glass.

The invention may be variously changed or modified in construction by the skilled mechanic in various features of detail, design, proportions, or otherwise, but all such changes are to be considered as within the scope of the following claims.

What I claim is:

1. In an apparatus for smoothing plate glass, the combination with a rotatable table, of supporting mechanism therefor having a vacuum cavity, rotating mechanism for the table, and means rotatably incorporated with the table for exhausting the air from said cavity, substantially as set forth.

2. In apparatus for smoothin plate glass, the combination with a rotata le support, of a glass supporting table having avacuum cavity communicating with the upper surface of the table, rotating mechanism for the support, and air exhausting mechanism incorporated with the rotatable table and communicating with the vacuum cavity therein, substantially as set forth.

7 3. In apparatus for smoothin plate glass, the combination with a rotata le support, of a glass supporting table having a vacuum cavity communicating with the upper surface of the table, rotating mechanism for the support, and air exhausting mechanism incorporated with the rotatable support and separably connected with the table and the vacuum cavity therein, substantially as set forth.

4. In apparatus for smoothin plate glass, the combination with a rotata le support, of a glass supporting table having a vacuum cavity communicating with the upper surface of the table, rotating mechamsm for the support, and air exhausting mechanism incorporated with the support consisting of a pump, a motor therefor, and

circulating means connecting the pump with the vacuum cavity of the table, substantially as set forth.

5. In apparatus for smoothin plate glass, the combination with a rotata le support, of a glass supporting table consisting of an upper and lower plate structure sealed together with an intervening cavity, said upper table 'having openings therethrough and supporting abutments, a pump, motor and reservoir mounted to revolve with the table and arran ed to exhaust the air from said cavity, an trolley conductor mechanism for supplying the motor, substantially as set forth.

In testimony whereof I hereunto aflix my signature in the presence of two witnesses.

EDWARD BAGNALL.

Witnesses:

C. M. CLARKE, FREDK. STAU'B. 

